The ACT had some major changes that finally came in 2012 (the Unit Titles (Management) Act 2011). Some useful fact sheets are here:
https://www.justice.act.gov.au/review/view/17/title/unit-titles
Changes include s.23 which enables sustainability infrastructure to be installed on common property (eg. a solar array or community garden) with a single proposal and ordinary resolution so long as various things are contained in the proposal. To boast for a moment: This came out of my submission to the review of the legislation. Our OC had twice tried to install a solar electric system on the roof of a shared common property carport roof that would cover the costs of all our common property lighting and match our consumption with as much renewable generation. Both times we did not get it passed even though a majority approved each time. A minority successfully blocked it. Our story got the legislation changed.
Another change renders invalid any by-law that prevents the installation of sustainability measures. So, for example, you can’t be told you can’t install double glazing or that you can’t have a clothes line and must use an electric drier or can’t put solar equipment on the roof of your townhouse.
Another change made it more explicit that the sinking fund can be used to anticipate and fund infrastructure upgrades and additions, not just purely maintenance.